FIELD OF THE INVENTION
The present invention relates to a novel form of certain hypnotic drugs and to their administration to mammals. They may be employed for any of the conventional purposes for which hypnotics are known, but especially for improving sleep.
Hypnotic drugs are a class of therapeutic agents which are commonly employed to induce and/or to prolong sleep. They may also be utilized to alleviate sleep disorders. Terms such as sedative, anti-anxiety agent, minor tranquilizer and anxiolytic are sometimes used somewhat interchangeably for such drugs because, in appropriate dosages, these hypnotics can produce similar effects.
There are a wide variety of hypnotic drugs. This term includes both barbiturates and non-barbiturates. Typical barbiturate hypnotics are aprobarbital and pentobarbital. Non-barbiturates recognized for their hypnotic activity include benzodiazepines; antihistamines having pronounced side effects such as diphenhydramine; serotonin initiators such as L-tryptophane; and various other drugs including ethinamate, chloral hydrate, ethchlorvynol, methyprylon and glutethimide. Their hypnotic effect is commonly attributed to a neurological mechanism involving depression of the central nervous system. That effect is also frequently accompanied by a mild reduction in such physiological functions as blood pressure and respiration.
PRIOR ART
Numerous hypnotic drugs are already known. Many, for example, are listed in the Physicians Desk Reference (PDR) published by Medical Economics Company, Inc. They are widely used therapeutically to improve sleep. Administration is generally performed either parenterally or, more usually, orally by means of pills, tablets and capsules. Their various uses are likewise well known.
Unfortunately, these drugs commonly exhibit a number of drawbacks when conventionally administered. Some have undesirable side effects. Many are inefficiently and variably absorbed from their current dosage forms. Further, the onset of their pharmacological activity is often delayed and/or the duration of that activity limited pursuant to ordinary oral, subcutaneous and/or intra-muscular administration.
Unlike the broad applicability of conventional routes of administration, the nasal delivery of therapeutic agents is a relatively recently discovered technique. It is also recognized only for specific agents. Representative disclosures of nasal administration of drugs include: U.S. Pat. No. 4,454,140 of Goldberg et al; U.S. Pat. No's. 4,428,883; 4,284,648; and 4,394,390 of Hussain and U.S. Pat. No. 4,624,965 of Wenig.
While nasal administration has become an accepted route of administration, the foregoing disclosures limit that mode of delivery to the specific drugs described. Moreover, it has been observed that many therapeutic agents cannot be usefully administered by this unusual route. Consequently, nasal administration remains a technique for which applicability is far from universal and the results unpredictable.